Also, add to this, Mack spent more time as the manager of a team than anyone else in baseball history by a country mile...
1901-50 Connie Mack, Athletics (50 seasons)
Mack’s entire career was legendary. During his time with the A’s, which began when he was just 38 years old, the team totaled nine pennants, with five of those resulting in World Series titles. Only two managers -- fellow Hall of Famers Joe McCarthy and Casey Stengel -- won more titles, with seven each.
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1902-32 John McGraw, Giants (31 seasons)
The 29-year-old McGraw signed with the Giants during the season in 1902 after the player/manager was released by the Orioles, beginning a tenure that would last until 1932. Primarily an infielder, he spent his first five years with the Giants as a player/manager before becoming solely the skipper. During his span with New York, the Giants won 10 pennants and converted three of those into World Series titles. The Giants had a .591 winning percentage during McGraw’s time in charge.
Source: MLB,
Skippers who stuck with 1 team the longest.